Sheet feeder interrupter control for address printing machine



8 Sheets-Sheet l INVENTOR ATTORNEY May 1967 T. J. MlTCHELL SHEET FEEDER INTERRUPTER CONTROL FOR ADDRESS PRINTING MACHINE Filed Jan. 14, 1966 THOMAS J MITCHELL BY T. J. MITCHELL SHEET FEEDER INTERRUPTER CONTROL FOR ADDRESS PRINTING MACHINE May 23, 1967 Filed Jan. 14, 1966 8 Sheets-Sheet 2 INVENTOR THOMAS JJ-MITCHELL BY ATTORNEY May 23, 1967 Filed Jan. 14, 1966 T. J. MITCHELL SHEET FEEDER INTEERUPTER CONTROL FOR ADDRESS PRINTING MACHINE 8 Sheets-Sheet 5 INVENTOR ATTORNEY THOMAS J. MITCHELL BY 8 Sheets- Sheet 4 T. J. MITCHELL SHEET FEEDER INTERRUPTER CONTROL FOR ADDRESS PRINTING MACHINE LNVENTOR THOMAS J. MITCHELL BY haw ATTORNEY g FIG. 3

May 23, 1967 Filed Jan. 14, 1966 FIG.7

SHEET FEEDER INTERRUPTER CONTROL FOR ADDRESS PRINTING MACHINE Filed Jan. 14, 1966 8 Sheets-Sheet 5 INVEINTORI THOMAS J. MITCHELL ATTORNEY May 23, 1967 T. J. MITCHELL 3,320,878

SHEET FEEDER INTERRUPTER CONTROL FOR ADDRESS PRINTING MACHINE Filed Jan. 14, 1966 8 Sheets-Sheet 6 KNVENTOR' QJOMAS 'J MITCHELL 7644; aw;

ATTORNEY May 23. 1967 T J. MITCHELL 3,320,878

SHEET FEEDER INTERRUPTER CONTROL FOR ADDRESS PRINTING MACHINE Filed Jan. 14, 1966 8 Sheets-Sheet 7 g THoMAs J. MICHELL -7%(;; 4/: w

ATTORNEYS INVENTOR May 23, 1967 Filed Jan. 14, 1966 -EENTER -52 MOTOR FEEEER /2&

MOTOR POWER SUPPLY T. J. MKTCHELL SHEET FEEDER I NTERRUPTER CONTROL FOR ADDRESS PRINTING MACHINE 8 Sheets-Sheet 8 ATTORNEY RECTIFIER 1 246 KAI lC' g 50 KC I A ,if

52 KB! I; f

y I w 248 4 2456 76 KO 2 X: 1+ KC 2 I KB I 1' 1' 2.1

3 M 5,5 Q94 n n \F /4Z /L X KA 3 (W Y 5 MM A INVENTOR THOMAS J. MITCHELL BY FIG" 8 United States Patent ice ware Filed Jan. 14, 1966, Ser. No. 520,622 1e Claims. c1. 101-57 This invention relates to automatic sheet feeders for printing machines of the type employing a series of printing plates which are fed automatically to a printing position and more particularly to an improvement in systems of the type described and claimed in US. Patent No. 2,359,852 issued Oct. 10, 1944-, to L. H. Morse for Printing Machine.

The Morse invention provided an automatic sheet feeder that could be moved into and out of operative relation ship with a printer of the kind commonly called an addresser-printer and which enabled the printer to be used more effectively by providing automatic feeding of sheets or forms to printing position when the volume of work to be performed was too great for manual sheet feeding. Although the separable feeder unit of Morse included a motor for operating sheet advancing belts and other moving parts, certain mechanisms thereof were driven by the printer through an involved system of mechanical linkages. Although this mechanical interconnection enabled the sheets to be fed automatically in cor rect time relationship with the operating cycle of the printer, it also added weight, bulk and cost to the sheet feeder unit. Moreover, mechanical. linkages have the added objective of introducing noise and limiting speed of operation. The latter is particularly true where the system employs reciprocating mechanisms such as levers and gear racks.

Accordingly the primary object of this invention is to provide a new and improved sheet feeder especially adapted for use with an addresser-printer and which when so used provides an automatic printing system that is an improvement over the invention of Morse disclosed in said US. Patent No. 2,359,852.

A more specific object of the invention is to provide an improved self-contained sheet feeder that is adapted to be placed in a predetermined operative relationship with an addresser-printer through simple, quickly made me chanical and electrical connections and which operates in timed relation to the printer under the control of an electrical system that not only permits a high rate of production but is adapted to automatically terminate or prevent operation on occurrence or absence of certain predetermined conditions.

Other objects and many of the attendant advantages of this invention will become apparent from the following detailed description which is to be considered together with the accompanying drawings wherein:

FIG. 1 is a fragmentary side elevational view of an addresser-printer equipped with a sheet feeder in accordance with the present invention, with certain operational components omitted or represented schematically for the sake of clarity and simplicity of description;

FIG. 2A is a longitudinal sectional view in elevation of the front half of the sheet feeder with the latter reversed 180 from its position in FIG. 1;

FIG. 2B is a longitudinal sectional view in elevation of the rear half of the sheet feeder taken from the same vantage point as FIG. 2A;

FIG. 3 is a side view in elevation on an enlarged scale of the front end of the sheet feeder positioned as in FIGS.

2A and 2B 3,320,878 Patented May 23, 1967 FIG. 4 is a fragmentary sectional view taken along line 4-4 of FIG. 2A showing the disposition of certain control switches;

FIG. 5 is a fragmentary plan view of the rear half of the sheet feeder;

FIG. 6 is a schematic perspective view of the printers operating mechanism and its operative relationship to an actuator switch assembly for the sheet feeder provided according to the present invention;

FIG. 7 is a side view in elevation of one of the switches of the sheet feeder actuater switch assembly; and

FIG. 8 is a diagram of the control circuits used in the illustrated embodiment of the invention.

It is to be appreciated that the sheet feeder provided according to the present invention is useable with a variety of conventional addresser-printers, e.g. Pitney-Bowes Models 35, 36, 40 and 50, which embody a reciprocatable printing platen moveable into and out of cooperating printing relationship with a printing plate removably disposed at a predetermined printing position. It is to be appreciated also that the sheet feeder of the present invention is designed so as to require only minor modification of the addresser-printer with which it is used. Accordingly only so much of the addresser-printer is described and illustrated herein as is required to explain its operational relationship to the novel sheet feeder.

Turning now to FIG. 1, the illustrated embodiment of the invention comprises a printing machine in the form of an addresser-printer 2 and a unitary automatic sheet feeder 4 constructed so as to be quickly and opcratively disposed in operative association with the printing machine. As is explained hereafter in greater detail, the sheet feeder may be quickly and easily removed when it is desired to feed printing sheets or forms manually instead of automatically. The addresser-printer comprises an enclosed frame 6 on which is mounted a table-top 8 that serves as a supporting surface upon which sheet feeder 4 is supported. The addresser-printer comprises a magazine 12 from which individual printing plates 14- of conventional form are advanced one by one along a printing plate gniideway beneath the table-top to an opening formed in the table-top 8 that defines a predetermined printing position. The guideway and opening are conventional and are omitted for the sake of clarity. The plates are advanced by a conventional plate feeder mechanism represented schematically at 16. After each printing plate has been used in a printing operation, it is removed from the printing position and delivered by mechanism 16 to a printing plate receptacle (not shown) attached to the enclosed frame 6. Cooperating with the printing plates to effect printing at the printing positions is a conventional platen mechanism identified generally by numeral 20 which comprises an L-shaped arm 22 whose bottom portion is pivotally connected to the table-top at a point 24 located to one side of and behind the printing position and whose upper portion extends forward diagonally at an angle of about 45 and terminates above the printing position. The end of the upper portion carries a platen assembly 26 disposed above the printing position. FIG. 1 illustrates the elevated inactive position of the platen mechanism; when the addresser-printer is operated, the platen mechanism is pivoted clockwise about point 24 to lower the platen assembly 26 to an active position wherein it presses a sheet or business form to be printed against a printing plate disposed at the printing position.

The platen assembly 26 may be of the type that carries an ink pad for directly making an image of the information impressed by the printing plate. Alternatively the platen assembly may merely provide a hard flat surface for pressing the paper sheet against the printing plate,

in which case an ink-bearing ribbon is disposed between the printing plate and the sheet to be printed. FIG. 1 schematically illustrates an ink-bearing ribbon 32 that is arranged to pass through the printing position from a supply spool 34 to a takeup spool 36. The ink-bearing ribbon is advanced by a suitable feeder mechanism 38 (see FIG. 6) that is coupled to one or both of the two spools. The feeder mechanisms for printing plates 14 and ink ribbon 32 and the platen mechanism are all operated by a suitable drive mechanism represented schematically at 40 that forms part of the addresser-printer. For the purposes of this invention drive mechanism 40 is also adapted to drive a mechanical linkage represented generally at 42 for operating a sheet feeder 'actuater switch assembly illustrated schematically at 44. Linkage 42 and switch assembly 44, described in greater detail below, constitute additions to the addresser-printer and function to initiate the time base for operation of various electrical relays in the control circuits of the sheet feeder shown in FIG. 8.

The printer also conventionally includes suitable electrical circuits which are modified by the sheet feeder control circuits. For convenience the control relays of both machines are mounted on a common chassis which may be attached to frame 6 of the printer as represented schematically in FIG. 1 by control relay assembly 46 or else attached to the frame of the sheet feeder. The printer also includes a-print pedal 48 which (through conventional means not shown) will initiate operation of the platen mechanism. As explained in greater detail below, when the feeder is connected to the printer, depressing pedal 48 will initiate operation of the platens mechanism if the printers control circuits have been properly conditioned by the feeder.

The primary components of the printers drive mechanism 40 are illustrated schematically in FIG. 6. The drive mechanism comprises a motor 52 that is coupled to a transmission 54 'by way of clutch 56 whose ope-ration is controlled by a clutch solenoid 58. Transmission 54 comprises an output shaft 60 that is connected to drive printing plate feeder 16, ink ribbon feeder 38 and printing platen mechanism 20. Further details of transmission 54 are not provided since such mechansms are well known to persons familiar with conventional addresser-printers. It is believed to suffice for the purposes of this specifica tion to state that during one cycle of operation of the transmission its output shaft 60 is rocked through a limited angle sufficient to reciprocate the printing platen mechanism.

The mechanical linkage 42 added to the printer for the purposes of this invention comprises a slotted crank 62 attached to output shaft 60 that is pivotally coupled to a rocker arm 64 mounted on a cam shaft 66 whose opposite ends are rotatably secured to frame 6. Cam shaft 66 carries four cams 68, 70, 72 and 74 that are positioned to trip four switches 76, 78, 80 and 82 respectively that make up the actuator switch assembly 44. Hereafter, switch 76 is referred as the document stop switch, switch 78 as the feed demand switch, switch 80 as the feed sensing switch, and switch 82 as the document sensing switch. The four cams are adapted by differently shaped cam surfaces 84 to actuate the four switches at different times in the operating cycle of the printer. These times are described in greater detail below. All four switches are adapted to be actuated during the return stroke of the printing platen which occurs on clockwise movement of shaft 60 (as seen in FIG. 6). To this end the actuating finger 86 (see FIG. 7) of each switch, e.g. switch 76, is provided with a lateral extension 88 to which is pivoted a small lever 90 carrying a roller 92. A tension spring 94 connected between finger 86 and lever 90 urges the latter clockwise about its pivot point (as seen in FIG. 7) to keep its bottom end in engagement with the end of finger 86. In other words the end of finger 86 functions as a stop for lever 90 so that it can rotate counterclockwise but not clockwise from the position shown in FIG. 7. Thus the adjacent cam on shaft 60 will actuate the switch when shaft 60 rotates counterclockwise as seen in FIG. 6 but on reverse motion of the shaft it will merely deflect lever without affecting the switch.

The sheet feeder unit in a broad sense comprises a frame structure which supports a supply magazine adjacent one end thereof for holding a supply of sheets to be printed, means for separating the sheets and feeding them one at a time into operative relationship to sheetadvancing means, guide means for receiving sheets from the advancing means and delivering them to a bridging structure that includes a plurality of sheet feeding belts for transporting the sheets across the table-top to a receiving hopper, and means for momentarily interrupting movement of each sheet at the printing position for the performance of a printing operation thereon.

Referring now to FIGS. 2A, 2B, 3, 4, and 5, the sheet feeding means comprises a frame consisting of a pair of front side plates 100, 101 and a pair of rear side plates 102, 103 that are connected by a pair of longitudinally extending side bars 104, 105. In practice these side plates are concealed by cover plates such as are shown at A and 102A in FIG. 1. The members of each pair of side plates are held in parallel spaced relation by transversely extending tie rods such as, but not limited to rods 106 and 108. The two front plates 100, 101 serve to support an adjustable supply hopper 110 plus a number of elements hereinafter described for removing sheets from the supply hopper and initiating their travel toward the printing position. More particularly, the front side plates 100, 101 support a booster roller 112, a starting or main feed roller 114 and an abrasive retard roller 116. Roller 112 serves to maintain the leading end of the foremost sheet in the hopper in position to be engaged and driven by the starting roller 114. Retard roller 116 serves to separate the leading sheet from the one immediately following and permit roller 114 to propel it forward into the nip of a demand feed roller 118 and two demand feed idler rollers 120. Appropriate gearing (not shown) connects the shafts on which rolls 112, 114, and 118 are mounted so that these rolls will rotate in synchronism with each other. In accordance with conventional practice, suitable means indicated generally at 122 are provided for varying the spacing between main feed roller 114 and retard roller 116 and similar means 124 are provided to vary the corresponding spacing between the demand feed roller 118 and idler rollers 120.

Referring now to FIG. 3, a motor 128 is mounted on the inner side of the right hand side plate 101. The output shaft 130 of the motor is coupled through a belt and pulley arrangement represented generally by numeral 132 (and including large pulley 133) and a chain and spocket arrangement identified generally by numeral 134 to a solenoid control clutch 136 of conventional design which also is mounted on the right hand side plate 101. Clutch 136 is mounted on the outer end of shaft 140 on which is mounted the demand feed roller 118. Solenoid 142 mounted on the same side plate 101 is connected through a linkage 144 to clutch 136. When solenoid 142 is energized it actuates clutch 136, thereby causing rotation of demand feed roller 118 and, through the aforementioned intervening gear train (not shown) shaft 140 causes synchronous rotation of rolls 112, 114 and 118. When the solenoid is deenergized, clutch 140 is disengaged and all of the aforementioned rolls immediately stop rotating.

Supported by and extending between the front side plates 100, 101 and rear side plates 102, 103 is a bridging structure 146 comprising means for receiving sheets delivered by rolls 118 and 120 and transporting them across the table-top through the predetermined printing position.

This bridging structure consists of two like portions 146A- and 146B, each of which comprises a metal guide member 148, a travelling belt 152, and a bogie strip 154. The bogie strip 154 rests on the upper run of the belt. Each bogie strip has a series of openings with a bogie roller 155 positioned in each opening for engagement with sheets transported by belt 152. In the normal course of operation sheets from rollers 118 and 120 are picked up by belts 152 which transport them across the table top. The documents are prevented from becoming airborne by bogie strips 154.

Each of the belts 152 is mounted on a drive roller 156 and an idler roller 158 which are carried by shafts rotatably supported by the front and rear side plates 100, 101 and 102, 103 respectively. An additional pair of idler rollers 160 and 162 mounted in a corresponding manner serve to keep the lower runs of the belts so that they will not engage the table-top. The belts are driven continuously by motor 128 operating through the belt and pulley assembly 132 whose pulley 133 is mounted on and drives the shaft of rollers 156.

The rear side plates further support an adjustable collecting hopper 116 which is positioned to receive printed sheets delivered by belts 152. Hopper 166 is provided with one or more resilient fingers 167 that serve to hold down sheets deposited therein by belts 152. As shown in FIG. 5 these rear side plates also serve as points of attachment for a pair of brackets 168 which rotatably support a pair of wheels 170. These wheels rest on the table-top 8 and serve to keep the rear side plates just out of contact with the table-top. The front side plates also are supported so as to just clear the table-top. In this case, as shown in FIGS. 1 and 2A, the desired support is achieved by means of a circular rail 172 that is supported at its ends by a pair of standards 174 (only one is shown) attached to the machine frame 6. Adjustably mounted on the front rail 172 (see FIGS. 1 and 2A) is a clamping device or locking assembly in the form of a clevis 176 that has a circular aperture 178 therein to receive rail 172. A hand-operated threaded knob 180 permits locking the clevis to the rail so as to prevent the sheet feeder from moving laterally relative to the table-top 8. The clamping device is formed with a suitable vertical slot which is adapted to receive the lower end of side plate 100 for lateral positioning of the latter. When the clevis 176 is released by backing oif screw 180, the sheet feeder can be moved sidewise on the table-top, thereby to facilitate properly positioning of a sheet with respect to the printing position.

Associated with the aforesaid sheet-feeding rolls at the front end of the feeder unit are two document sensing switches 182 and 184 (see FIG. 4). Switch 182 is a doubles switch and functions to sense whether more than one sheet at a time is advanced by rollers 114 and 116. This switch has a finger 186 provided with a roller 188 at its bottom end in position to be engaged by sheets passing out from between rollers 114 and 116. Switch 184 is a hopper feed switch and its function is to sense whether a sheet is ready to be advanced by rollers 118 and 120 to the sheet guides 148. Switch 184 has a depending actuating finger 190 that is positioned proximate to demand feed roller 118 so as to be en ged by a sheet at that position.

In addition to switches 182 and 184, two other switches 194 and 196 (FIGS. 2B and 5) are mounted on the sheet feeder unit. These switches are document sensors and are adjustably positioned on the metal guide strips 148. Each is adapted to be locked in place by a thumb screw 198 which engages the guide strips. Each of switches 194 and 196 has an actuating finger 200 that is disposed to engage sheets being transported by belts 152. In prac tice these switches are located downstream of the printing position so as to sense each document leaving the print area en route to the receiving hopper 166. Only one document sensing switch is used at any one time.

Also forming part of the feeder unit is a document stop assembly which comprises a pair of transversely extending bars 202 to which is slidably attached a longitudinally extending support bar 204. At the rear end of bar 284 is an integral bracket 206 that is grooved to fit under bars 202. Support bar 204 is provided with a tapped hole to accept a thumb screw 208 whose stem extends down between bars 202 and through a suitable hole in bracket 206. The thumb screw 208 is screwed tight to clamp bars 202 between its head and bracket 206. Also forming part of the document stop assembly is a block 212 that is slidably positioned on support bar 204. A thumb screw 214 locks block 212 on bar 204. Block 212 is undercut to accommodate a solenoid 218 and has two aligned holes in which a transversely extending pivot shaft 220 is rotatably mounted. Shaft 220 has a projecting pin 222 that is pivottally attached to the armature of solenoid 218. Shaft 220 also has a plurality of like diametrically extending holes in two of which are positioned thin rods 226. Thumb screws 228 attached to shaft 220 permit longitudinal adjustment of rods 226. The forward ends of rods 226 are fitted with right-angled document stop members 230 of suitable design. With solenoid 218 deenergized, the stop members 230 are in lowered position where they can intercept a document and hold it in the print position. The exact position in which the document is stopped is determined by the location of block 212 and the effective length of rods 226. When the solenoid is energized, the stop members are lifted to release the intercepted document. The released document then is transported by the constantly-moving belts 152 to the receiving hopper 166.

Turning now to FIG. 8, the various switches and solenoids already mentioned plus other electrical components hereinafter described are connected so as to provide controlled feeding, movement, stopping and release of sheets. The circuit includes a rectifier 234 which is connected along with motor 128 of the sheet feeder so as to be controlled by the ON-OFF power switch 236 of printer motor 52. The negative and positive terminals of rectifier 234 are connected to two bus bars 238 and 240 which serve as terminal strips for a plurality of parallel control circuits. A first circuit is provided by cam-operated document stop switch 76 and document stop solenoid 218. A manually operated normally open button type switch 244 (marked START FEED) is connected on one side to bus bar 238 and on the opposite side between switch '76 and solenoid 218. A second normally closed switch 246 is ganged for operation with switch 244. Switch 246 is connected between the two bus bars in series with a relay KA and a pair of its normally open contracts KA1. The junction of solenoid KA and its contacts KAI also is connected to bus bar 238 (a) via cam operated feed sensing switch and a pair of normally closed contacts KC1 of a relay KC, (b) via cam operated document sensing switch 82 and the normally closed contacts KDl of a relay KD, and (c) via doubles switch 182. Another circuit between the two bus bars is provided by on or the other of document sensing switches 194, 196 connected in series with relay KD. In this connection it is to be noted that two normally closed jacks 248A and 24813 are provided for switches 194 and 196 respectively. For the purposes of this description, switch 194 is plugged into jack 248A and it is connected electrically to relay KD through the normally closed contacts of jack 24813. The junction of jack 24813 with relay KD is connected back to bus bar 238 via the norma1- ly closed contacts of the cam operated feed demand switch 78 and the normally open contacts KDZ of relay KD. Relay KC is connected between the two bus bars in series with a second set of normally open contacts KC2 of relay KC and a pair of normally open contacts K131 of a relay KB. The junction of contacts KC2 and KBI is connected to the normally open contact of switch 78. The feeder clutch solenoid 142 is connected between the two bus bars via a series connection with a second set of normally closed contacts KB2 of relay KB and a second set of normally closed contacts KAZ of relay KA. A connection is also provided between bus bar 238 and the junction of contacts KB2 and KA2 via a normally open reset button switch 250, a normally closed reset button switch 252, and a diode 254. Switches 250 and 262 are ganged to switches 244 and 246. The junction of switches 250 and 252 is connected to the junction of relay KC and contacts KBl. Relay KB is connected to the two bus bars via hopper feed switch 184. The printers clutch solenoid 58 and a set of normally open contacts KA3 of relay KA form another circuit between the two bus bars.

Following is an analysis of the foregoing circuitry during operation of the sheet feeder. When switch 236 is closed, power is supplied simultaneously to motors 52 and 128 and rectifier 234. The rectifier provides DC. power of appropriate voltage to the control relays and solenoids and instantaneously the feeder clutch solenoid 142 is energized. The first document inserted in the feed hoper actuates the hopper feed switch 184. This in turn causes relay KB to be energized, which in turn causes the feeder clutch solenoid 142 to be deenergized. Depressing the button of start feed switch 244 operates switches 244, 246, 250 and 252 which are mechanically connected. Switch 244 energizes the document stop solenoid 218 and switch 250 energizes relay KC. Relay KC is maintained through contacts KC2 and KBl. Releas' ing the button of feed switch 244 deenergizes the docu' ment stop solenoid 218 and switch 252 closes and thus energizes the feeder clutch solenoid 142. The first document in the hopper is transported to the print area allowing hopper feed switch 184 to open. Relay KB and thus relay KC is deenergized. The feeder clutch solenoid 142 remains energized via normally closed contacts KB2.

The second document in the feed hopper actuates hopper fee-d switch 184. Relay KB becomes energized and feeder clutch solenoid 142 deenergizes. Depressing the print pedal 48 will imprint the first document. Document stop switch 76 actuates after 220 of the printer cycle from home position of shaft 60. Actuation of document stop switch 76 energizes the stop solenoid 218. The document proceeds along the guides'150 and actuates sensing switch 194 (or alternate switch 196 if it is used), allowing relay KD to energize. At 235 of the printer cycle, feed demand switch 78 is actuated, thus energizing relay KC. Simultaneously the feeder clutch solenoid 142 energizes. At 245 of the printer cycle, feed sensing switch 80 is actuated and this energizes relay KA if relay KC has not been energized. Feed demand switch 78 is released at about 250 of the print cycle and relay KD will remain energized if either document sensing switch 194 or alternate switch 196 is actuated. Document stop switch 76 opens after about 270 of the print cycle, deenergizing document stop solenoid 218. At about 265 feed sensing switch 80 opens. Document sensing switch 82 is actuated at about 345 and will energize relay KA if relay KD has not been energized. Document sensing switch 82 opens at about 355. The second document is fed to the print area and the hoper feed switch 184 is opened. Relays KB and KC are deenergized and the feeder clutch solenoid 142 remains energized. 'The third document in the feed hopper actuates the hopper feed switch 184. Relay KB is energized, causing feeder clutch solenoid 142 to deenergize.

During continuous print operation the feeder will continue to function as above until one of the operations now to be described occurs to stop the system.

The last document in the feed hopper will initiate the following sequence: (a) hopper feed switch 184 is not actuated by a doucment, (b) relay KB does not energize; (c) feeder cluth solenoid 142 remains energized; (d) feed demand switch 73 closes so does not energize;

3 (e) feed sensing switch closes and relay KA is energized; and (f) the printer clutch solenoid 58 is energized and feeder clutch solenoid 142 is deenergized. Step (f) causes the printer to stop.

If a document is late entering the feed rolls and does not actuate hopper feed switch 184, the sequence outline in (b) through (f) above will occur to stop the machine.

Double document feed malfunction will cause following to occur: (a) doubles switch 182 is actuated; (b) relay KA is energized; (c) printer clutch solenoid 53 is energized; and (d) feeder clutch solenoid 142 is deenergized.

If a document fails to actuate transport sensing switch 194 (or alternate switch 196 if connected) after release by the document stops, the machine is stopped as follows: (a) relay KD is not energized; (b) document sensing switch 82 is actuated; (c) relay KA is energized; (d) the printer clutch solenized 58 is energized; and (e) the feeder clutch solenoid 142 is deenergized. With the foregoing system, in order to deenergize relay KA it is necessary to either depress button switch 244 (reset) or place the main power switch 236 in the OFF position.

Once relay KA is deenergized to effect deenergization of printer clutch solenoid 58, operating pedal 48 will reactivate the printer.

It is to be understood that the invention is not limited in its application to the details of construction and arrangement of parts specifically described or illustrated, and that within the scope of the appended claims, it may be practiced otherwise than as specifically described or illustrated.

I claim:

1. In combination: (1) a printing machine comprising a table top with a printing position thereon to which printing plates are fed, a printing mechanism with impression means for making printed impressions from said printing plates at said printing position, a first electric motor, and a drive mechanism, powered by said first motor for cyclically operating said printing mechanism: and (2) an automatic sheet feeder comprising a frame having a bridging structure that extends across said table top over said printing position, said frame being separable from said machine, means moveably supporting said frame so that it can move sidewise relative to said table top, a supply hopper on said frame for holding a supply of sheets to be printed, a second electric motor supported by said frame, feeder means for separating said sheets and feeding them one at a time to said bridging structure, electrically controlled feeder drive means for driving said feeder means from said second motor, sheet transporting means for advancing separated sheets along said bridging structure to an operating position over said printing position and thereafter out of said operating position, means for driving said sheet transporting means from said second motor, electrically operated stop means for adjustably stopping each sheet at said operating position, said stop means mounted on said frame, a first control circuit for said electrically controlled feeder drive means including switch means actuated by said drive mechanisms for cyclically operating said feeder drive means so that sheets are separated and fed from said supply hopper at spaced intervals, a second control circuit for said electrically operated stop means including switch means actuated by said drive mechanism for cyclically operating said stop means so that each sheet is stopped at said printing position for a predetermined time during which said printing mechanism is operated to produce an iimpression on the stopped sheet from a printing plate at the printing position and thereafter is released for movement away from printing position by said sheet transporting means, means for sensing an interruption in the normal one at a time movement of sheets, and electrical control means responsive to said sensing means for deactivating at least one of the following: said driye mechanism and said feeder drive means. I

2. The combination of claim 1 wherein said last-mentioned means also is operative to deactivate said stop means.

3. The combination of claim 1 wherein said sheet transporting means comprises at least a pair of endless belts, and said sensing means includes an electrical sensing member supported by said bridging structure and positioned to sense whether a sheet released by said stop means is transported away from said printing position by said endless belts.

4. The combination of claim 1 wherein said sheet feeder comprises a plurality of rollers, and further wherein said feeder drive means rotates said rollers in a direction to feed sheets out of said hopper, said feeder drive means includes an electromechanically actuated clutch, and further wherein said first control circuit cyclically operates said clutch.

5. The combination of claim 1 wherein said sensing means includes switches adapted to sense the presence or absence of sheets at predetermined points in their normal path of movement from said supply hopper to and beyond said printing position, and means for operating said last-mentioned control means according to the condition of said switches at predetermined times in the cycle of operation of said drive mechanism.

6. The combination of claim 1 wherein said stop means comprises a support bar attached to said frame above the level of said sheet transporting means and a stop assembly secured to said support bar, said stop assembly comprising a stop member, means supporting said stop member for pivotal movement between a first sheet-stopping position and a second sheet-passing position, and a solenoid connected to pivot said stop member to one of its said first and second positions when energized and back to the other of its said first and second position when deenergized.

7. An automatic sheet feeder of the character described adapted for operative association with a printing machine of the type having a table top in which a printing position is provided, a printing platen mechanism, and means for causing said printing platen mechanism to undergo a predetermined cycle of operation, said sheet feeder comprising electrically controlled feeder means operable to separate and transport sheets one by one into and then out of said printing position in predetermined timed relation to operation of said platen, and electrically operated means for terminating operation of said feeder means on failure of said feeder means to transport sheets according to said predetermined time relation, said electrically operated means comprising a plurality of sheet sensing elements positioned at predetermined points along the normal path of movement of sheets that are separated and transported by said feeder means, said sheet sensing elements operative to provide electrical signals indicative of the presence or absence of sheets at said points, means including conditionable relay means for terminating operation of said feeder means in response to signals from said sensing elements occurring during a predetermined condition of said relay means, and mechanically operated means for conditioning said relays according to a time base related to the cycle of operation of said platen mechanism.

8. A sheet feeder as defined by claim 7 wherein said relay-conditioning means comprises at least one switch connected to said relay means and a cam mechanism for actuating said at least one switch, and means adapted to drive said cam mechanism from said drive means.

9. A sheet feeder as defined by claim 8 wherein at least one of said sheet sensing means is a switch positioned downstream of said printing position and having an actuating member in position to be tripped by a sheet transported by said feeder means.

10. In combination with a printing machine of the type having a table top in which a printing position is provided, means for delivering printing plates to said printing position, a platen mechanism operative for making a printed impression from a printing plate onto a sheet when said printing plate and sheet are located at said printing position, a first motor, and first electrically controlled drive means for operating said platen mechanism from said first motor; a sheet feeder comprising a frame supported on said table top, a supply hopper supported by said frame, feeder mechanism carried by said frame including first feeder means for separating sheets from said hopper and second transporting means for advancing them one by one to said printing position and thereafter out of said printing position, said frame, supply hopper and feeder mechanism moveable as a unit along said table top in a direction at right angles to the direction in which sheets are advanced to said printing position by said second transporting means, operative sheet-stopping means for stopping each sheet at said printing position for a printing operation and then releasing each sheet for advancement away from said printing position by said transporting means, a second motor carried by said frame, second electrically controlled drive means for operating said feeder means from said second motor, electrical control means for operating said sheet stopping means and said second drive means in timed relation with said first drive means, said electrically controlled means including switches actuated by said first drive means, means for detecting improper separation and advancement of sheets by said feeder mechanism, and electrical control means for terminating operation of said first and second drive means on occurrence of improper separation or advancement of sheets by said feeder mechanism.

References Cited by the Examiner UNITED STATES PATENTS 2,359,852 10/1944 Morse 101-56 2,814,248 11/1957 Federwitz a- 101134.5 2,908,220 10/1959 Eichenbaum et al. 101-132.5

WILLIAM B. PENN, Primary Examiner. WILLIAM F. MCCARTHY, Examiner. 

1. IN COMBINATION: (1) A PRINTING MACHINE COMPRISING A TABLE TOP WITH A PRINTING POSITION THEREON TO WHICH PRINTING PLATES ARE FED, A PRINTING MECHANISM WITH IMPRESSION MEANS FOR MAKING PRINTED IMPRESSIONS FROM SAID PRINTING PLATES AT SAID PRINTING POSITION, A FIRST ELECTRIC MOTOR, AND A DRIVE MECHANISM, POWERED BY SAID FIRST MOTOR FOR CYCLICALLY OPERATING SAID PRINTING MECHANISM: AND (2) AN AUTOMATIC SHEET FEEDER COMPRISING A FRAME HAVING A BRIDGING STRUCTURE THAT EXTENDS ACROSS SAID TABLE TOP OVER SAID PRINTING POSITION, SAID FRAME BEING SEPARABLE FROM SAID MACHINE, MEANS MOVEABLY SUPPORTING SAID FRAME SO THAT IT CAN MOVE SIDEWISE RELATIVE TO SAID TABLE TOP, A SUPPLY HOPPER ON SAID FRAME FOR HOLDING A SUPPLY OF SHEETS TO BE PRINTED, A SECOND ELECTRIC MOTOR SUPPORTED BY SAID FRAME, FEEDER MEANS FOR SEPARATING SAID SHEETS AND FEEDING THEM ONE AT A TIME TO SAID BRIDGING STRUCTURE, ELECTRICALLY CONTROLLED FEEDER DRIVE MEANS FOR DRIVING SAID FEEDER MEANS FROM SAID SECOND MOTOR, SHEET TRANSPORTING MEANS FOR ADVANCING SEPARATED SHEETS ALONG SAID BRIDGING STRUCTURE TO AN OPERATING POSITION OVER SAID PRINTING POSITION AND THEREAFTER OUT OF SAID OPERATING POSITION, MEANS FOR DRIVING SAID SHEET TRANSPORTING MEANS FROM SAID SECOND MOTOR, ELECTRICALLY OPERATED STOP MEANS FOR ADJUSTABLY STOPPING EACH SHEET AT SAID OPERATING POSITION, SAID STOP MEANS MOUNTED ON SAID FRAME, A FIRST CONTROL CIRCUIT FOR SAID ELECTRICALLY CONTROLLED FEEDER DRIVE MEANS INCLUDING SWITCH MEANS ACTUATED BY SAID DRIVE MECHANISMS FOR CYCLICALLY OPERATING SAID FEEDER DRIVE MEANS SO THAT SHEETS ARE SEPARATED AND FED FROM SAID SUPPLY HOPPER AT SPACED INTERVALS, A SECOND CONTROL CIRCUIT FOR SAID ELECTRICALLY OPERATED STOP MEANS INCLUDING SWITCH MEANS ACTUATED BY SAID DRIVE MECHANISM FOR CYCLICALLY OPERATING SAID STOP MEANS SO THAT EACH SHEET IS STOPPED AT SAID PRINTING POSITION FOR A PREDETERMINED TIME DURING WHICH SAID PRINTING MECHANISM IS OPERATED TO PRODUCE AN IIMPRESSION ON THE STOPPED SHEET FROM A PRINTING PLATE AT THE PRINTING POSITION AND THEREAFTER IS RELEASED FOR MOVEMENT AWAY FROM PRINTING POSITION BY SAID SHEET TRANSPORTING MEANS, MEANS FOR SENSING AN INTERRUPTION IN THE NORMAL ONE AT A TIME MOVEMENT OF SHEETS, AND ELECTRICAL CONTROL MEANS RESPONSIVE TO SAID SENSING MEANS FOR DEACTIVATING AT LEAST ONE OF THE FOLLOWING: SAID DRIVE MECHANISM AND SAID FEEDER DRIVE MEANS. 